Inspection means



A ril 5, 1938; L. J. MOLLOY ET AL 2,

3 INSPECTION MEANS Filed May 22, 1936 .EQA

Bnventors Patented Apr. 5, 1938 UNITED STATES PATENT OFFICE INSPECTION MEANS Leo J. Molloy, Baltimore, Md., and Louis K: Morrison, Norfolk, Va.

Application May 22, 1936, Serial No. 81,310

11 Claims.

This invention relates to means for facilitating the inspection and determination of conditions within tanks, receptacles, and systems, for example, those in the art relating to fire extinguishers and systems.

The invention has particular application to fire extinguishing spray tanks, apparatus and systems, and it enables an observer to readily In order to maintain portable fire extin-' 20 guishers, or other fire extinguishing systems and apparatus, in a condition of maximum efficiency, it is generally necessary to periodically change or renew their fire extinguishing charges. This necessity is well recognized; for example, the fire 25 insurance companies require their policy holders to regularly renew the contents of their (the policy holders) fire extinguishers. If the policy holders do not comply with this requirement, their insurance protection is subject to revision 30 or termination. Users of fire extinguishers,

therefore, issue instructions that the fire extinguishing charges should be periodically renewed. These instructions are impart the result of a desire for eificient fire protection and in part the 5 result of a desire to preserve the fire insurance contract.

Despite any rule or instruction that an oflicial (whether of a factory, railroad or business house), may issue to his employees with regard 40 to conditioning of his companys fire extinguishing apparatus, the employees, as shown by ex-' perience, will not, or fail to, change or renew the fire extinguishing charge at one or another of the times designated for this conditioning of the 45 apparatus. I-Ieretofore, it has been difficult to detect this evasion of the company rules, as the 55 which will exhibit a visible characteristic to in-- dicate its period of maximum effectiveness and the time when it was placed in the fire extinguishing apparatus or system.

A' further object is to provide fire extinguishing. apparatus or other liquid containing systems 5 with light-transmitting means which will permit observation and. illumination of the vvisible characteristics of the fire extinguishing charge or substance within the apparatus or system.

Another object is: to provide an improved inspection-attachment for use with tanks, receptacles, andother apparatus, where it is desired to observe the conditions existing therein.

It is a-further object to provide means which will facilitate the determination as to whether the contents of e particular fire extinguishing apparatus or system has been periodically renewed, where such renewal is essential to maintain the apparatus in av condition of maximum efiiciency.

Other objects, uses and advantages of. this 2 invention will be more apparent from the following description and the appended drawing wherein,

Fig. I is an elevationalview of a conventional portable fire extinguisher provided with an embodiment of this invention, parts of the extinguisher being broken away for the purposes of illustration.

Fig. II is an enlarged vertical cross sectional View ofthe inspection window shown in Fig. I, being takenon line II-II of Fig. I.

Fig. III is a perspective View of the thimble element shown in Figs. I and'II.

I Referring to the drawing, the fire extinguisher l is of the conventional portable type which is provided with afiuid charge 2 comprising asolution of sodium bicarbonate and with a small bottle of'a suitable acid (not shown). The invention, however, may obviously be applied to 4 other typesof fire extinguishing apparatus.

The fire extinguisher I! has the usual bottom wall 3 which is setback or spaced from the bottom edges of the extinguisher side walls to provide a recessed base for the fire extinguisher.

The charge 2, Whether it-is a solution of sodium bicarbonate or some other fire extinguishing substance, has in general a maximum effectiveness of onlylimited'duration. The practice, therefore, is to periodically renew 'or replace the charge. The stability or resistance to deterioration of the charge 2 generally determines the length of the period it may be left in the fire extinguishing apparatus without the efficiency of the apparatus falling below a desired minimum; Heretofore,

it has been difficult to determine if the charge 2 has been left in the fire extinguishing apparatus beyond the limit of its period of maximum effectiveness. It is, therefore, a feature of this invention to provide fire extinguishing charges which have visible identifying characteristics for indicating whether the charge is new or has been left in the apparatus beyond its period of maximum effectiveness. The characteristics referred to may be the color of the charges. This color characteristic may be secured by the addition of a suitable dye, or other color producing agent, to the charge 2 at the time it is prepared for the fire extinguishing apparatus.

For the purposes of a specific example, it may be assumed that the maintenance of fire extinguishing apparatus in a condition of maximum efficiency requires renewal of the fire extinguishing charge 2 every year. According to a preferred embodiment of this invention, different colors serve to distinguish the different fire extinguishing charges to be used during successive years, and if any charge is not renewed at the end of a year, its color characteristic will dis- .close this fact to an inspector during his round of inspection.

In order that the color or other indicating characteristic of the charge 2 may be observed without opening the fire extinguishing apparatus, an inspection window is provided in a wall of the extinguisher. This inspection window, which may be placed in the bottom wall 3 of the apparatus as shown in the drawing, has a hollow cup or thimble-shaped member ID of transparent glass, or of other suitable light-transmitting material, through which the indicating characteristics of the charge 2 are visible. The closed end II of the thimble-shaped member I is tapered, or otherwise suitably shaped, for a purpose to be described, and the open end of the thimble member ID has a flange I2.. The thimble member IE! is mounted in a frame member I3, which has inner and outer annular shoulders as shown in Fig. II. A ring I4 having threaded engagement with the interior wall of the frame member I3 serves to clamp the thimble flange I2 and a pair of ring-shaped gaskets I5 and I6 (of any suitable material) against the internal shoulder of the frame member I3 and to maintain the thimble member II) and frame member I3 in assembled relation. The gaskets I5 and I6 are positioned at opposite sides of the thimble flange I2 to seal the joint and to protect the thimble flange I2. vided with a gasket I1 and a clamping ring I8 the latter having threaded engagement with the external wall of the frame member I3.

The inspection window, as described above, comprises a unit which may be installed in extinguishers already in service or in extinguishers at thetime of their manufacture. In order to install the inspection window unit, a suitable aperture is made in a wall, for example, the bottom 3, of the extinguisher, and the frame member I3 is inserted in the aperture. The ring I8 may now be positioned to clamp the extinguisher wall 3 and gasket I'I against the external shoulder of the frame member I3. The open end of the thimble member I0 is now in communicae tion with the interior of the fire extinguisher I so that part of its charge 2 will flow into the thimble member ID where it may be conveniently inspected.

The closed end II of thimble I0, when the inspectionwindow unit is installed in the fire ex- The inspection window is also protinguisher, will project beyond the bottom wall 3 but within the limits of the extinguisher as defined by the projecting side walls constituting its base. The projecting side Walls, while affording a large measure of protection against accidental damage to the transparent thimble ID, will not interfere with the examination of the thimble member ID and its contents nor prevent examination at close range. The fire extinguisher base does prevent an observer from illuminating and inspecting the thimble contents along lines normal to the longitudinal axis of the thimble member I0. The tapered end I I of the thimble, however, overcomes this drawback attendant the placement of the inspection device in an out-ofthe way and protected position. This tapered end I I permits illumination, as by flashlight, and observation from positions (such as indicated by the letters A and B) beyond the bottom edges of the extinguisher base and-along lines (shown in the drawing as extending between the tapered end I I and the positions A and B) approximately normal to the tapered end II. The examination may, therefore, be readily conducted along lines normal to the inner and outer surfaces of the thimble member I0, and will not be interfered with by light refraction which occurs when a beam of light passes obliquely from one medium into another. The closed end II may obviously be provided with other suitable shapes, such as hemispherical, which will serve the same purpose as the tapered form of thimble end.

The inspection device of this invention will obviously facilitate inspections and eliminate the necessity for moving or handling the extinguisher provided with same even if the extinguisher is hung in a difiicultly accessible place, such as when it is within a wall recess or mounted on a bracket in a corner of a room.

The present invention also obviously has application to other than fire extinguishing apparatus and is useful wherever the problems solved thereby are present.

It will be understood that the foregoing description is illustrative, and that the appended claims are intended to cover such other embodiments as are within the scope, of the invention.

We claim:

1. The combination with a portable fire extinguisher having its bottom wall set back from the bottom edges of its side walls and containing a fire extinguisher charge which is to be periodically renewed to maintain the extinguisher in a condition of maximum efficiency and which has a visible characteristic to indicate effectiveness,v

of an inspection window in the form of a lighttransmitting thimble shaped member supported by said bottom wall with the open end of the member communicating with the interior of the extinguisher to permit a part of said charge to enter the member, said member having a closed end extending below said bottom wall but within the limits of the extinguisher defined by said side wall and bottom edges, said closed end being suitably shaped at its periphery to permit illumination and inspection of the contents in said member from beyond said side wall bottom edges and along lines inclined with respect to the axis of the member but approximately normal to the surface at said periphery.

2. An inspection device for use with a fire extinguisher or extinguishing system having a fire extinguishing charge which is to be periodically renewed to maintain the extinguisher in a condition of maximum efficiency and which has a 75 a visible characteristic indicative of its period of maximum effectiveness, said device comprising a frame member having internal and external shoulders and adapted to be set within an opening in a wall of a fire extinguisher, a transparent hollow thimble-shaped member having a flanged open end set within said frame member and its closed end extending beyond said frame member, means to clamp the flange of said thimble-shaped member against said internal shoulder, and means to clamp said. external shoulder to said fire extinguisher wall.

3. An inspection device for use with a fire extinguisher or extinguishing system having a fire extinguishing charge which is to be periodically changed. to maintain the extinguisher in a condition of maximum efficiency and which has a visible characteristic indicative of its period of maximum effectiveness, said device comprising a frame member having internal and external shoulders and adapted tobe set within an opening in a Wall of a fire extinguisher, a transparent hollow thimble-shaped member having a flanged open end set within said frame member and its closed end extending beyond said frame member, a ring having threaded engagement with the interior wall of said frame member to clamp the flange of said thimbleshaped member against said internal shoulder, and a ring having threaded engagement with the exterior wall of said frame member to clamp said external shoulder to said fire extinguisher wall.

4. An inspection device for use with a fire extinguisher or extinguishing system having a fire extinguishing charge which is to be periodically changed to maintain the extinguisher in a condition of maximum efiiciency and which has a visible characteristic indicative of its period of maximum effectiveness, said device comprising a frame member adapted to be placed at an opening in a wall of a fire extinguisher, a transparent hollow thimble-shaped member, and a pair of clamping rings having threaded engagement with said frame member to separately clamp said thimble-shaped member and extinguisher wall tosaid frame member.

5. An inspection device for attachment to receptacles,- tanks and the like comprising a frame member having internal and external shoulders and adapted to be set within an opening in a wall of said tank, a transparent hollow thimbleshaped member having a flanged open end set within said frame member, said hollow member having its closed end tapered and extending beyond said frame member, a ring having threaded engagement with the interior wall of said frame member to clamp the flange of said hollow memher to said internal shoulder, and a ring having threaded engagement with the exterior wall of said frame member to clamp said external shoulder to said tank wall.

6. The combination with a portable fire extinguisher of the type having its interior normally open to the atmosphere and adapted to receive charge components such as a solution of sodium carbonate and a substance for reacting therewith which require periodic renewal to maintain the extinguisher in a condition of maximum efficiency and which upon inversion of the extinguisher react to liberate a pressure producing gas for expelling the extinguisher charge under pressure, of an inspection chamber for a wall of the extinguisher, said chamber having a closed end projecting beyond said wall, and an opening in communication with the interior of; the.=extinguisher to permit; part of said charge to-enter said:chamber,,said'chamber having at least a portion thereof: of light-transmitting material-:to'permit observationof the chamber contents from, without the extinguisher.

'7. The combination with aportable fire extinguisher of the. type having, its interior normally open to the atmosphere and adapted to receive charge componentssuch as a solution of sodium carbonate and a substance for reacting therewith which require periodic renewal to maintain the extinguisher in a condition of maximum efiiciency and which upon inversion of the extinguisher react to liberate a pressure producing gas for expelling the extinguisher charge under pressure, of an inspection window for a wall of the extinguisher, said window being in the form of a light-transmitting thimble-shaped member having its closed end projecting beyond said wall and its open end in communication with the interior of the extinguisher to permit part of said charge to enter said member for inspection from without the extinguisher.

8. The combination with a portable fire extinguisher of the type having its interior normally open to the atmosphere and adapted to receive charge components such as a solution of sodium carbonate and a substance for reacting therewith which require periodic renewal to maintain the extinguisher in a condition of maximum efficiency and which upon inversion of the extinguisher react to liberate a pressure producing gas for expelling the extinguisher charge under pressure, of an inspection chamber for a wall of the extinguisher, said chamber having a closed end projecting beyond said wall, and an opening in communication with the interior of the extinguisher to permit part of said charge to enter said chamber, said chamber having areas of light transmitting material and in different planes to permit illumination and observation of the contents within said chamber from different points having spaced relation about the chamber.

9. The combination with a portable fire extinguisher of the type having its interior normally open to the atmosphere and adapted to receive charge components such as a solution of sodium carbonate and a substance for reacting therewith which require periodic renewal to maintain the extinguisher in a condition of maximum eificiency and which upon inversion of the extinguisher react to liberate a pressure producing gas for expelling the extinguisher charge under pressure, of light-transmitting means comprising a thimble-shaped member secured to the bottom wall of the extinguisher and having its interior communicating with the interior of said extinguisher to permit part of said charge to enter said member for inspection from without the container.

10. The combination with a portable fire extinguisher of the type having its interior normally open to the atmosphere and adapted to receive charge components such as a solution of sodium carbonate and a substance for reacting therewith which require periodic renewal to maintain the extinguisher in a condition of maximum efficiency and which upon inversion of the extinguisher react to liberate a pressure producing gas for expelling the extinguisher charge under pressure, of an inspection window in the form of a light-transmitting thimble-shaped member having its open end communicating with the interior of the extin- 11. The combination with a portable fire ex- V tinguisher of the type having a reservoir open to the atmosphere and adapted to contain charge components which react upon inversion of the extinguisher to liberate a gas for exerting pressure to discharge the extinguisher contents and which require periodic renewal to maintain the extinguisher in a condition of maximum efficiency, of a solution stored in said reservoir as one of said charge components, said solution being provided with a coloring material that is arbitrarily selected as indicative of the date when the solution was placed in the extinguisher, and transparent inspection means in communication with the interior of the extinguisher reservoir and projecting outwardly from a wall thereof to contain and to present to view exteriorly of the extinguisher a portion of the solution contained within the extinguisher in order to determine by the color of the solution the length of time it has remained in the extinguisher.

LEO J. MOLLOY.

LOUIS K. MORRISON. 

